The present invention relates to a dishwasher, in particular a domestic dishwasher, comprising an attachment device for receiving intake water and an execution control device in which are held one or more washing programs for controlling an execution of one or more wash cycles.
A domestic dishwasher which is known from practice for the purpose of washing dishes has a closable washing compartment, into which the dishes can be inserted for the purpose of cleaning. The known domestic dishwasher further comprises an attachment device which can be attached to an external fresh water source for the purpose of receiving fresh water. In practice, the fresh water source is a water line of a water supply that is installed in a building. The attachment device is connected to the washing compartment in such a way that the fresh water received by the attachment device can be carried into the washing compartment, where it is used as dishwashing water.
The domestic dishwasher also has a circulating pump, which allows dishwashing water that collects in a lower region of the washing compartment to be sprayed onto the dishes by means of a spray device. The dishwashing water then returns to the lower region of the washing compartment due to gravity, thereby forming a closed circulation loop.
An electrical heating device is arranged in the circulation loop in this case, allowing the dishwashing water to be brought to a predetermined temperature during dishwashing. In order that the heating device can be selectively controlled in this case, provision is further made for a sensor for the temperature of the dishwashing water. The known dishwasher also has drain pump, which allows dishwashing water to be pumped out when it is no longer required.
For the purpose of controlling the execution of a washing process, which is usually referred to as a wash cycle, the dishwasher has an execution control device. In this case, an execution control device is understood to mean a control device which controls an execution of a wash cycle according to predetermined steps.
The steps required to carry out a wash cycle, and the transition conditions for the change from one step to a subsequent step, are specified in a washing program in this case. In this case, a washing program contains all the information that is required by the execution control device for the purpose of automatically controlling the execution of a wash cycle. This results in a high level of operating convenience, since the operator, after starting a washing program, no longer needs to worry about the further execution of the wash cycle.
A typical wash cycle comprises (in this chronological sequence) a prewash cycle, a cleaning cycle, an intermediate wash cycle, a rinsing cycle and a drying cycle. In this case, the intermediate wash routine can be omitted or replaced (partly or completely) by a drain routine if applicable.
After the operator has started a corresponding washing program, the prewash cycle is started, wherein intake water (in particular fresh water) is introduced into the dishwasher by corresponding activation of the intake water receiving device. Corresponding activation of the circulating pump then causes the intake water to be circulated as dishwashing water in order to remove heavy soiling from the dishes. After a predetermined time, at least some of the now soiled dishwashing water is pumped out as a result of corresponding activation of the drain pump, and the prewash cycle is terminated.
At the start of the subsequent cleaning cycle, further intake water (in particular fresh water) is introduced into the washing compartment as a result of renewed activation of the receiving device. Said intake water is heated, in a heating phase of the cleaning cycle, by activation of the heating device. During the heating phase of the cleaning cycle, detergent is usually added to the dishwashing water that is held in the washing compartment at this stage, by means of a detergent dosing device which is controlled by the execution control device. Furthermore, during the heating phase of the cleaning cycle, the circulating pump is controlled in such a way that the dishwashing water is circulated so that even stuck-on soiling can be removed from dishes. When the temperature of the wash cycle reaches a value that is predetermined by the washing program, this is detected by means of the sensor for the temperature of the wash cycle, whereupon the execution control device switches off the heating device. After completion of the heating phase of the cleaning cycle, a postwash or post-cleaning phase of the cleaning cycle is carried out for a predetermined period, during which the dishwashing water continues to be circulated. At the end of the postwash phase, the drain pump is activated again such that at least some of the dishwashing water from the cleaning cycle is pumped out.
At the start of the intermediate wash cycle which now follows if applicable, the dishwashing water in the washing compartment is topped up again with intake water via the receiving device, in particular fresh water. The dishwashing water of the intermediate wash cycle is not usually heated, but is circulated by means of the circulating pump. In particular, the intermediate wash cycle allows detergent residues to be removed from the dishes. After expiry of a predetermined period, at least some of the dishwashing water from the intermediate wash cycle, which now includes the detergent residues, is pumped out.
At the start of the subsequent rinsing cycle, the receiving device is activated again for the purpose of introducing intake water, in particular fresh water, into the washing compartment. This is mixed with rinse-aid by a rinse-aid dispenser, heated by means of activating the heating device and circulated by means of corresponding activation of the circulating pump. When an intended temperature is reached, the circulating pump and the heating device are switched off. The dishwashing water is then pumped out via the drain pump and the rinsing cycle is terminated. The rinsing cycle is intended in particular to prevent the formation of stains on the cleaned dishes, and this is essentially achieved by the chemical properties of the rinse-aid. The rinsing cycle is also intended generally to prepare the dishes for the subsequent drying cycle, by heating them to a relatively high temperature.
During the subsequent drying cycle, during which no new dishwashing water is introduced into the washing compartment, any still-adhering dishwashing water evaporates due to the high temperature of the dishes. This water then condenses primarily on the walls of the washing compartment and collects in a lower region of the washing compartment. From there, the dishwashing water is pumped out after a predefined time by means of the drain pump and the drying cycle is terminated.
The basic execution of a typical wash cycle described above can be varied in many and diverse ways. For example, different time constants or different temperatures can be specified. It is also possible to omit individual partial wash cycles, e.g. the prewash cycle and/or intermediate wash cycle, or to repeatedly carry out individual partial wash cycles, e.g. the prewash routine, intermediate wash cycle or cleaning cycle, or to insert a plurality of partial wash cycles in series, e.g. a plurality of prewash routines, intermediate wash cycles and/or cleaning routines. In this way, the intended execution of the wash cycle can be adapted to various applications scenarios.
In the case of modern dishwashers, provision is therefore usually made for a plurality of washing programs for controlling the execution of a wash cycle. In this case, the operator has the possibility of selecting a suitable washing program depending on the application scenario. For example, in addition to a normal washing program, provision can be made for an intensive washing program in order to achieve a greater cleaning effect, an energy-saving washing program in order to reduce the energy requirement and/or a delicate washing program for delicate treatment of the dishes. Provision can also be made for a further washing program which is adapted to the volume of the load and/or the type of dishes. All of the cited washing programs can also be provided in a quick-wash variant which is intended to reduce the overall duration of the wash cycle.
In this case, each of the washing programs is configured in such a way that, taking into consideration further specifications such as e.g. maximal wash cycle duration or maximal stress on the dishes, a defined cleaning and/or drying effect can be achieved with maximal efficiency using a wash cycle which is based on the relevant washing program. In this case, the efficiency corresponds to the relationship between the washing result that is achieved and the effort that is required to achieve it.
The known dishwasher has the disadvantage that the actual execution of a wash cycle is dependent not only on the selected washing program, but also on environmental conditions. Consequently, the desired cleaning and/or drying effect can only be ensured in an efficient manner if the dishwasher is operated under standard conditions. However, if the dishwasher is operated under different conditions, the desired cleaning and/or drying effect will either be exceeded or not achieved. Although too great a cleaning and/or drying effect results in a satisfactory washing result on one hand, it simultaneously results in a reduction of the efficiency of the dishwasher, and in particular the energy efficiency. Conversely, too modest a cleaning and/or drying effect results in an unsatisfactory washing result.